White balance enclosure for use with a multi-viewing elements endoscope

ABSTRACT

The specification describes a white balance enclosure for use with a tip of a multi-viewing elements endoscope. The white balance enclosure is used to provide a reference white background to the plurality of viewing elements when the tip is positioned within the white balance enclosure and a white balance circuit is used to calculate and store reference white balance values based on white field/test feed signals generated by the plurality of viewing elements exposed to the reference white background.

CROSS REFERENCE

The present application is a continuation application of U.S. patentapplication Ser. No. 14/271,234, entitled “White Balance Enclosure forUse with a Multi-Viewing Elements Endoscope” and filed on May 6, 2014,which relies on U.S. Provisional Patent Application No. 61/820,650, ofthe same title and filed on May 7, 2013, for priority.

The present application is also related to U.S. patent application Ser.No. 14/263,896, entitled “Video Processing In A Compact Multi-ViewingElement Endoscope System” and filed on Apr. 28, 2014 and to U.S.Provisional Patent Application No. 61/936,562, entitled “Method andSystem for Video Processing In A Multi-Viewing Element Endoscope” andfiled on Feb. 6, 2014.

All of the above mentioned applications are herein incorporated byreference in their entirety.

FIELD

The present specification generally relates to a multi-viewing elementsendoscope, and more particularly to a white balancing enclosure,designed as a cap in one embodiment, for consistently and uniformlyapplying a white balance adjustment to a picture image or videogenerated by multiple viewing elements.

BACKGROUND

An endoscope conventionally comprises an elongated tubular shaft, rigidor flexible, having a video camera and/or fiber optic lens assembly atits distal end. The shaft is connected to a handle and viewing is madepossible via an external screen. Various surgical tools may be insertedthrough a working channel in the endoscope for performing differentsurgical procedures.

Endoscopes, such as colonoscopes, that are currently being usedtypically have a front camera for viewing the internal organ, such asthe colon, an illuminator, a fluid injector for cleaning the cameralens, and a working channel for insertion of surgical tools, forexample, for removing polyps found in the colon. Often, endoscopes alsohave fluid injectors (“jet”) for cleaning a body cavity, such as thecolon, into which they are inserted. The illuminators commonly used arefiber optics, which transmit light generated remotely, to the endoscopetip section.

The inside of internal organs such as the stomach, colon or cecum isgenerally reddish. As a result, when internal organs are observed usingan endoscope without having appropriate color adjustment of pictureimage or video signals, the captured color images and videos carry asubstantially reddish hue. In a conventional endoscope, in order toprevent this problem, a white balance adjustment is carried out; thatis, values, factors or coefficients for making the intensity of thepicture image or video signals for three primary colors such as red (R),green (G) and blue (B) equal, are applied to the video signal generatedfrom a camera. In addition, white balance adjustment is also performedto make the intensity of the picture image or video signals for fouradditional colors, such as yellow (Ye), cyan (Cy), magenta (Mg), andgreen (G), equal for charge coupled device (CCD) sensor based processes.Such values, factors, or coefficients are generated by imaging areference white color object.

However, for a multi-viewing elements endoscope, all cameras need to becalibrated for white balance consistently and uniformly. There is thus aneed in the art for enabling consistent and uniform white balancecalibration of all viewing elements of a multi-viewing elementsendoscope. There is also a need in the art for a novel and easy to usereference white object that exposes all viewing elements of amulti-viewing elements endoscope to the same reference white level forpurposes of white balance calibration.

SUMMARY

The following embodiments and aspects thereof are described andillustrated in conjunction with systems, tools and methods, which aremeant to be exemplary and illustrative, not limiting in scope.

In accordance with an embodiment of the present specification, a tipsection of a multi-viewing element endoscope comprises at least onefront-pointing viewing element and at least one front illuminatorassociated therewith; at least one side-pointing viewing element and atleast one side illuminator associated therewith; a front working channelconfigured for insertion of a medical tool; and at least one sideservice channel configured for insertion of medical tools. Themulti-viewing element endoscope is connected to a main control unit thatgoverns a plurality of operational functionalities of the endoscope. Atleast one display may be connected to the main control unit andconfigured to display images and/or video streams received from theviewing elements of the multi-viewing element endoscope.

In some embodiments, each of the front-pointing viewing element and theat least one side-pointing viewing element comprises an image sensorsuch as, but not limited to, a charge coupled device (CCD) or acomplementary metal oxide semiconductor (CMOS).

In one embodiment, the camera board of the main control unit circuitboard outputs video feeds, received from the multiple viewing elementsof the endoscope, to a white balancing circuit. In one embodiment, theendoscope tip comprises three viewing elements (one front-looking andtwo side-looking viewing elements). Therefore, in one embodiment, theoutput video feeds comprise three video feeds corresponding to the threeviewing elements of the endoscope.

In one embodiment, a white balance circuit is implemented as part of thefield-programmable gate array (FPGA) on the main control unit circuitboard.

In another embodiment, a white balance circuit is implemented as part ofa digital signal processor (DSP) for video signals that is placed intoan integrated circuit (DSP IC) or into the FPGA.

In another embodiment, a white balance circuit is implemented as part ofa digital signal processor (DSP) for video signals that is built into acomplementary metal oxide semiconductor (CMOS) video sensor.

In an embodiment, the present specification is directed toward a devicefor enabling uniform white balancing of a first viewing element and asecond viewing element in an endoscopic tip, comprising: a housingdefining an enclosed volume and having an opening for receiving saidendoscopic tip, wherein said opening has a first diameter configured tosnugly receive said endoscopic tip such that external light is preventedfrom entering through said opening when said endoscopic tip is insertedtherein and wherein the enclosed volume has a surface area that is at apredefined distance from the second viewing element when said endoscopictip is inserted therein; and a member extending out from the surfacearea and within the enclosed volume, wherein said member is configuredto position said first viewing element at the predefined distance fromthe surface area.

The first viewing element and second viewing element each have a fieldof view, wherein the surface area of the enclosed volume within saidfirst field of view of the first viewing element may be a first color,wherein the surface area of the enclosed volume within said second fieldof view of the second viewing element may be a second color, and whereinthe first and second colors may be equal.

Further, a portion of the surface area of the enclosed volume withinsaid second field of view may be at least 10 millimeters from the secondviewing element.

In some embodiments, the enclosure comprises at least one indicator onsaid surface area, wherein said indicator is positioned on said surfacearea such that it is visible via said at least one side viewing element,indicating to a user that said tip is properly positioned within saidenclosure.

The member may be a stopper component that extends inwardly from saidsurface area and is configured to contact a distal face of saidendoscopic tip.

In an embodiment, the housing may comprise at least a first portion anda second portion which join together to form said housing.

In an embodiment, the device includes a coupling mechanism for securingsaid housing to a control unit of an endoscope system. The couplingmechanism may be at least one of a hanger or magnetic coupler.

In some embodiments, the enclosed volume has a cylindrical or sphericalshape.

Further, the housing defining said enclosed volume may be of a seconddiameter which is equal to said first diameter plus twice said distance.

In another embodiment, the present specification is directed toward awhite balancing system for enabling uniform white balancing of a firstviewing element, a second viewing element, and a third viewing elementin a tip of an endoscope, wherein the first viewing element ispositioned on a distal face of said tip and the second and third viewingelements are positioned on sides of said tip, said white balancingsystem comprising: a housing defining an enclosed volume and having anopening for receiving said endoscopic tip, wherein said opening has afirst diameter configured to snugly receive said endoscopic tip suchthat external light is prevented from entering through said opening whensaid endoscopic tip is inserted therein, wherein the enclosed volume hasa surface area that is at a first predefined distance from the secondviewing element and at a first predefined distance from the thirdviewing element when said endoscopic tip is inserted therein; and amember extending out from the surface area and within the enclosedvolume, wherein said member is configured to position said first viewingelement a second predefined distance from the surface area.

In an embodiment, the first predefined distance and second predefineddistance may be the same or different.

Further, the white balance system may comprise a control unit connectedto said endoscope and comprising a white balance circuit for whitebalance processing of images obtained by said first, second, and thirdviewing elements; and at least one display connected to said controlunit for displaying said processed images.

The white balance enclosure includes, in some embodiments, a timerassociated with said white balance circuit for controlling a time periodof said white balance processing. The time period may be in the range of3 to 5 seconds.

In some embodiments, the white balance enclosure further comprises asplitter associated with said white balance circuit for splitting awhite balance command to a digital signal processor associated with eachviewing element.

In an embodiment, the first viewing element, second viewing element, andthird viewing element each have a field of view and wherein the surfaceareas of the enclosed volume within said fields of view comprise a whitecolor.

In an embodiment, a portion of said surface area of the enclosed volumewithin a second field of view is at least 10 millimeters from the secondviewing element and wherein a portion of said surface area of theenclosed volume within a third field of view is at least 10 millimetersfrom the third viewing element.

Further, the housing defining said enclosed volume may be of a seconddiameter which is equal to said first diameter plus twice said distance.

The member may be a stopper component that extends inwardly from saidsurface area and is configured to contact a distal face of saidendoscopic tip.

In yet another embodiment, the present specification is directed towarda method for performing a white balance for images obtained from atleast one front viewing element and at least one side viewing element ofa tip of an endoscope, said method comprising: inserting a distal tip ofsaid endoscope comprising said front viewing element and side viewingelement into an enclosure, said enclosure comprising a three-dimensionalbody defining an inner area and having a proximal end, a distal end, aninner surface, an outer surface, a distal wall, and an opening at saidproximal end; positioning said tip within said inner area of saidenclosure such that said front viewing element and side viewing elementare within said enclosure and each of said front and side viewingelements is positioned an equal distance from said inner surface of saidenclosure; instructing a control unit to white balance said front andside viewing elements, wherein said control unit calculates whitebalance values using digital signal processors on said control unit andstores white balance values in memory to be used for later processing ofimages; and, removing said endoscope tip from said enclosure.

In accordance with an embodiment, a timer counts 3 to 5 seconds. Acontroller applies previously calibrated and stored white balancevalues/factors to selectively amplify or attenuate the respective red,green and blue or yellow, cyan, magenta, and green signals of each videofeed. During the white balancing process, a digital signal processor(DSP) compares actual values of red, green, and blue or yellow, cyan,magenta, and green from the CCD or CMOS sensor, which are received froma white picture, with theoretical values of red, green, and blue oryellow, cyan, magenta, and green from a mathematical model of a whitepicture. Corrective parameters obtained from the comparison are used forred, green, and blue or yellow, cyan, magenta, and green adjustmentamplifiers and are stored in a DSP memory. The white balanced signalsare then displayed on one, two, or three monitors.

In one embodiment, a cap is designed to be conveniently slipped/slidonto and enclose the multiple viewing elements endoscopic tip. Inalternate embodiments, the white balance enclosure is designed in theform of a clasp that securely encloses and attaches to the endoscopictip, or in the form of a snap which snug-fits onto the endoscopic tip.

In alternate embodiments, the shapes of the first and second portions ofthe white balance enclosure are square or any other suitable shape thatfacilitates the endoscopic tip to be equidistant from the inner walls ofthe enclosure. Additionally, the first and second portions can be ofdifferent shapes—for example, the first inner portion can be cylindricalwhile the second inner portion is rectangular, square, or vice versa.

In accordance with an aspect of the present specification, the interiorof the white balance enclosure is isolated from the influx of exteriorlight, to avoid creating uneven shadows and illumination in the interiorof the enclosure and to prevent parasitic external illumination fromnon-endoscopic light sources/spectrums.

The aforementioned and other embodiments of the present invention shallbe described in greater depth in the drawings and detailed descriptionprovided below.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features and advantages of the present invention will beappreciated, as they become better understood by reference to thefollowing detailed description when considered in connection with theaccompanying drawings, wherein:

FIG. 1 shows an exploded view of a tip section of a multi-viewingelements endoscope, according to some embodiments;

FIG. 2A shows a front perspective view of a tip section of amulti-viewing elements endoscope, according to some embodiments;

FIG. 2B shows a rear perspective view of a tip section of amulti-viewing elements endoscope, according to some embodiments;

FIG. 3 shows a cross-sectional view of a tip section of a multi-viewingelements endoscope, according to some embodiments;

FIG. 4 shows a multi-viewing elements endoscopy system, according tosome embodiments;

FIG. 5A is a block diagram illustrating one embodiment of an overallvideo processing architecture;

FIG. 5B is a block diagram illustrating an embodiment of a whitebalancing circuit;

FIG. 6A is a perspective view of a white balance enclosure in accordancewith an embodiment of the present specification;

FIG. 6B is another perspective view of a white balance enclosure inaccordance with an embodiment of the present specification;

FIG. 6C is a cross-sectional view of one embodiment of a white balanceenclosure showing the tip of a multi-viewing element endoscopepositioned therein;

FIG. 6D is yet another perspective view of a white balance enclosure inaccordance with an embodiment of the present specification;

FIG. 6E is still another perspective view of a white balance enclosurein accordance with an embodiment of the present specification; and

FIG. 7 is a flow diagram showing exemplary steps of one embodiment ofusing the white balance enclosure to calibrate/white balance multipleviewing elements of an endoscope.

DETAILED DESCRIPTION

The present specification is directed towards multiple embodiments. Thefollowing disclosure is provided in order to enable a person havingordinary skill in the art to practice the invention. Language used inthis specification should not be interpreted as a general disavowal ofany one specific embodiment or used to limit the claims beyond themeaning of the terms used therein. The general principles defined hereinmay be applied to other embodiments and applications without departingfrom the spirit and scope of the invention. Also, the terminology andphraseology used is for the purpose of describing exemplary embodimentsand should not be considered limiting. Thus, the present invention is tobe accorded the widest scope encompassing numerous alternatives,modifications and equivalents consistent with the principles andfeatures disclosed. For purpose of clarity, details relating totechnical material that is known in the technical fields related to theinvention have not been described in detail so as not to unnecessarilyobscure the present invention.

It is noted that the term “endoscope” as mentioned to herein may referparticularly to a colonoscope and a gastroscope, according to someembodiments, but is not limited only to colonoscopes and/orgastroscopes. The term “endoscope” may refer to any instrument used toexamine the interior of a hollow organ or cavity of the body.

Reference is now made to FIG. 1, which shows an exploded view of a tipsection 200 of a multi-viewing elements endoscope assembly 100 accordingto an embodiment. An aspect of some embodiments relates to multi-viewingelements endoscope assembly 100 having tip section 200 equipped with oneor more side service channels. Tip section 200 may be turned by way offlexible shaft (not shown), which may also be referred to as a bendingsection, such as, but not limited to a vertebra mechanism. According toan embodiment, tip section 200 of an endoscope includes a tip cover 300,an electronic circuit board assembly 400 and a fluid channelingcomponent 600.

Electronic circuit board assembly 400 is, in one embodiment, configuredto carry a front-looking viewing element 116, a first side-lookingviewing element 116 b and a second side-looking viewing element on theopposite side of the first side looking viewing element. The twoside-looking viewing elements may be similar to front-looking viewingelement 116 and may include a charge coupled device (CCD) or acomplementary metal oxide semiconductor (CMOS) image sensor with optics.

Further, electronic circuit board assembly 400 is, in one embodiment,configured to carry front illuminators 240 a, 240 b, 240 c, which areassociated with and in communication with front looking viewing element116, and are positioned to essentially illuminate the fields of view offront-looking viewing element 116.

In addition, electronic circuit board assembly 400 is, in oneembodiment, configured to carry a first set of side illuminators 250 aand 250 b, which are associated with and in communication with sidelooking viewing element 116 b, and are positioned to essentiallyilluminate the fields of view of side looking viewing element 116 b.Electronic circuit board assembly 400 is, in one embodiment, alsoconfigured to carry a second set of side illuminators, which areassociated with and in communication with a second side looking viewingelement, which are similar to side illuminators 250 a and 250 b.

Front illuminators 240 a, 240 b, 240 c, first set of side illuminators250 a and 250 b, and the second set of side illuminators may optionallybe discrete illuminators and may include a light-emitting diode (LED),which, in some embodiments, may be a white light LED, an infrared lightLED, a near infrared light LED, an ultraviolet light LED or any otherLED. In various embodiments, white balance is only possible forendoscopes using white light LEDs.

The term “discrete”, concerning discrete illuminator, may refer to anillumination source which generates light internally, in contrast to anon-discrete illuminator, which may be, for example, a fiber opticmerely transmitting light generated remotely.

Reference is now made to FIGS. 2A and 2B, which show a perspective viewof a tip section 200 of a multi-viewing elements endoscope assembly 100according to an embodiment. Tip cover 300 is configured to fit over theinner parts of the tip section 200 (including electronic circuit boardassembly 400 and fluid channeling component 600 seen in FIG. 1), thusproviding protection to the internal components housed within the innerparts. In some embodiments, tip cover 300 includes a front panel 320having a front optical assembly 256, corresponding to front lookingviewing element 116 seen in FIG. 1. Front optical assembly 256 includesa plurality of lenses (or, in one embodiment, the plurality of lenses isassembled on the CCD or CMOS), static or movable, which can provide afield of view of up to essentially 180 degrees. Front optical assembly256, in one embodiment, can provide a focal length of up toapproximately 110 millimeters.

Referring to FIGS. 1, 2A, and 2B simultaneously, the optical axis offront looking viewing element 116 is substantially directed along thelong dimension of the endoscope. However, since front looking viewingelement 116 is typically a wide angle viewing element, its field of viewmay include viewing directions at large angles with respect to itsoptical axis. Additionally, front panel 320 may include optical windows242 a, 242 b and 242 c of illuminators 240 a, 240 b and 240 c,respectively. It should be noted that the number of illumination sourcesused for illumination of the field of view may vary in otherembodiments.

In addition, front panel 320 may include a working channel opening 340of a working channel 640, which is discussed in further detail below.

Jet channel opening 344 of jet channel 644 is, in one embodiment,located on front panel 320 of tip cover 300. Jet channel 644 may beconfigured for providing a high-pressure jet of fluid, such as water orsaline, for cleaning the walls of the body cavity.

Also located on front panel 320 of tip cover 300 is injector opening 346of injector channel 646 having a nozzle 348 aimed at front opticalassembly 256. Injector channel 646 is configured, in one embodiment, toinject fluid (liquid and/or gas) to wash contaminants such as blood,feces and other debris from front optical assembly 256 of front lookingviewing element 116. Optionally, in other embodiments, injector channel646 is configured for cleaning front optical assembly 256 and one, two,or all of optical windows 242 a, 242 b, and 242 c. Injector channel 646may be fed by fluid such as water and/or gas, which can be used forcleaning and/or inflating a body cavity.

Side optical assembly 256 b, corresponding to first side looking viewingelement 116 b, is, in one embodiment, located on sidewall 362 of tipcover 300 and is similar to front optical assembly 256. Further,sidewall 362 also houses optical windows 252 a and 252 b of illuminators250 a and 250 b, corresponding to first side looking viewing element 116b. Also on the sidewall 362 of tip cover 300, on the opposing side toside optical assembly 256 b, are an optical assembly and optical windowsfor a second side looking viewing element, which, in some embodiments,are similar to side optical assembly 256 b and optical windows 252 a and252 b of illuminators 250 a and 250 b corresponding to first sidelooking viewing element 116 b. The white balance system of the presentspecification can be used with endoscopes having a front viewing elementand one or more side viewing elements.

The optical axis of first side looking viewing element 116 b isessentially oriented perpendicular to the long dimension of theendoscope. However, since side looking viewing element 116 b istypically a wide angle viewing element, its field of view may includeviewing directions at large angles relative to its optical axis.

In addition, side injector opening 266 of side injector channel 666 islocated at the proximal end of sidewall 362 in one embodiment.Optionally, a nozzle cover 267 is configured to fit side injectoropening 266. Additionally, nozzle cover 267 may include a nozzle 268which is aimed at side optical assembly 256 b and configured forinjecting fluid to wash contaminants such as blood, feces and otherdebris from side optical assembly 256 b of side looking viewing element116 b. The fluid may include gas, which is used for inflating a bodycavity. Optionally, nozzle 268 can be configured for cleaning both sideoptical assembly 256 b and optical windows 252 a and/or 252 b.

According to some embodiments, side injector channel 666 is configuredto supply fluids for cleaning any of the tip elements (such as anyoptical assembly, windows, illuminators, and other elements).Optionally, injector channel 646 and side injector channel 666 are fedfrom the same fluid channel.

It is noted that according to some embodiments, although tip section 200is presented herein showing one side thereof, the opposing side mayinclude elements similar to the side elements described herein (forexample, side looking viewing element, side optical assembly,injector(s), nozzle(s), illuminator(s), window(s), opening(s) and otherelements).

In some embodiments, sidewall 362 forms of an essentially flat surface,which assists in directing the cleaning fluid injected from injectorchannel 666 toward side optical assembly 256 b and optical windows 252 aand/or 252 b. Lack of such a flat surface may result in dripping of thecleaning fluid along the curved surface of tip section 200 of theendoscope, without performing the desired cleaning action.

It is noted that according to some embodiments, tip section 200 mayinclude more than one side looking viewing element. In this case, theside looking viewing elements may be installed such that their field ofviews are substantially opposing. However, different configurations anda varied number of side-looking viewing elements are possible within thegeneral scope of the current specification.

According to some embodiments, there is provided herein an endoscope(such as but not limited to a colonoscope and/or gastroscope) thatincludes (in a tip section thereof), in addition to a front viewingelement and one or more side viewing elements, and in addition to afront working channel that is configured for insertion of a medical(such as surgical) tool, optionally, at least one side service channelthat is configured for insertion of a medical tool. Thus, in oneembodiment, the fluid channeling component includes a side servicechannel 650 having a side service channel opening 350.

Reference is now made to FIG. 3, which, in accordance with anembodiment, shows a cross-sectional view of a tip section 370 of amulti-viewing elements endoscope. Tip section 370 includes afront-pointing image sensor 372, such as a charge coupled device (CCD)or a complementary metal oxide semiconductor (CMOS) image sensor.Front-looking image sensor 372 is, in one embodiment, mounted on aprinted circuit board 376, which may be rigid or flexible. Printedcircuit board 376 is configured to supply front-looking image sensor 372with necessary electrical power and signals such as clock,synchronization, etc., and to derive still images and/or video feedscaptured by the image sensor. Printed circuit board 376 is connected toa set of electrical cables which, in one embodiment, is threaded throughan electrical channel running through the elongated shaft of theendoscope. Front-looking image sensor 372 and a lens assembly 374, whichin one embodiment, is mounted on top of image sensor 372, provide thenecessary optics for receiving images. Lens assembly 374 may include aplurality of lenses, static or movable, for providing a field of view ofat least 90 degrees and up to essentially 180 degrees. Front-lookingimage sensor 372 and lens assembly 374, with or without printed circuitboard 376, may be jointly referred to as a “front-looking viewingelement”.

One or more discrete front illuminators 378 are, in some embodiments,placed next to lens assembly 374 for illuminating its field of view.Optionally, discrete front illuminators may be attached to the sameprinted circuit board on which the front-pointing image sensor ismounted.

Optionally, tip section 370 further includes a side-looking image sensor382, such as a charge coupled device (CCD) or a complementary metaloxide semiconductor (CMOS) image sensor. Side-looking image sensor 382is, in one embodiment, mounted on a printed circuit board 386, which maybe rigid or flexible. Printed circuit board 386 is configured to supplyside-looking image sensor 382 with necessary electrical power andsignals such as clock, synchronization, etc., and to derive still imagesand/or video feeds captured by the image sensor. Side-looking imagesensor 382 and a lens assembly 384, which in one embodiment, is mountedon top of image sensor 382, provide the necessary optics for receivingimages. Side-looking image sensor 382 and lens assembly 384, with orwithout printed circuit board 386, may be jointly referred to as a “sidelooking viewing element”.

One or more discrete side illuminators 388 are, in some embodiments,placed next to lens assembly 384 for illuminating its field of view.Optionally, discrete front illuminators may be attached to the sameprinted circuit board on which the side-looking image sensor is mounted.

In another configuration, the printed circuit boards employed in thepresent specification may optionally be a single printed circuit boardon which both front and side-looking image sensors are mounted. For thispurpose, the printed circuit board is essentially L-shaped.

Front and side-looking image sensors 372 and 382 may be similar oridentical in terms of, for example, field of view, resolution, lightsensitivity, pixel size, focal length, focal distance and/or the like.Further, there may be two side-pointing image sensors in otherembodiments.

Optionally, side-looking image sensors and their respective lensassemblies are advantageously positioned relatively close to the distalend surface of tip section 370. For example, a center of theside-looking viewing element (which is the center axis of side-lookingimage sensor 382 and lens assembly 384) is positioned approximately 7 to11 millimeters from the distal end surface of the tip section. This isenabled by an advantageous miniaturizing of the front and side-lookingviewing elements which allows for enough internal space in the tipsection for angular positioning of the viewing elements withoutcollision. Persons of ordinary skill in the art should note that inaccordance with an embodiment, the multi-viewing elements endoscopecomprises one, two, or more than two side-looking viewing elements alongwith a front-looking viewing element.

Reference is now made to FIG. 4, which shows a multi-viewing elementsendoscopy system 401. In one embodiment, system 401 includes amulti-viewing elements endoscope 402. Multi-viewing elements endoscope402 may include a handle 404, from which an elongated shaft 406 emerges.Elongated shaft 406 terminates with a tip section 408, such as thatdescribed with respect to FIGS. 1, 2A, and 2B, which can be maneuveredby way of a bending section 410. Handle 404 is used for maneuveringelongated shaft 406 within a body cavity; the handle may include one ormore knobs and/or switches 405 which control bending section 410 as wellas functions such as fluid injection and suction. Handle 404 may furtherinclude a working channel opening 412 through which surgical tools maybe inserted as well as one or more side service channel openings.

A utility cable 414 is used to connect handle 404 and a main controlunit 416. In an embodiment, utility cable 414 includes therein one ormore fluid channels and one or more electrical channels. The electricalchannel(s) may include at least one data cable for receiving videosignals from the front and side-pointing viewing elements, as well as atleast one power cable for providing electrical power to the viewingelements and to the discrete illuminators. In some embodiments, theelectrical channel(s) also include cables for clocking andsynchronization signals and a cable for control of the CCD or CMOS imagesensors. In various embodiments, the above functions are combined intoone cable or separated into multiple cables.

The main control unit 416 governs a plurality of operationalfunctionalities of the endoscope. For example, the main control unit 416may govern power transmission to the tip section 408 of endoscope 402,such as for the tip section's viewing elements and illuminators. Themain control unit 416 may further control one or more fluid, liquidand/or suction pumps, which supply corresponding functionalities toendoscope 402. One or more input devices, such as a keyboard 418, can beconnected to main control unit 416 for the purpose of human interactionwith the main control unit 416. In another configuration, an inputdevice, such as a keyboard, may optionally be integrated with the maincontrol unit in a same casing.

A display 420 can be connected to main control unit 416 and configuredto display images and/or video streams received from the viewingelements of multi-viewing elements endoscope 402. Display 420 isoptionally configured to display a user interface for allowing a humanoperator to set various features of system 401.

Optionally, the video streams received from the different viewingelements of multi-viewing elements endoscope 402 can be displayedseparately on display 420, either side-by-side or interchangeably(particularly, the operator may switch between views from the differentviewing elements manually). Alternatively, these video streams may beprocessed by main control unit 416 to combine them into a single,panoramic video frame, based on an overlap between fields of view of theviewing elements.

In another optional configuration, two or more displays may be connectedto main control unit 416, each for displaying a video stream from adifferent viewing element of the multi-viewing elements endoscope 402.

FIG. 5A is a flow diagram detailing how a controller unit 520 of themain control unit operatively connects with the endoscope 510 and thedisplay units 550. Display units 550 are described above with respect toFIG. 4 as display 420. Referring to FIG. 5A, controller unit 520comprises a camera board 521 that transmits appropriate commands tocontrol the power supply to the LEDs 511 and to control the operation ofimage sensor 512 (comprising one or more viewing elements), such as acharge coupled device (CCD) as shown in FIG. 5A or, in otherembodiments, a complementary metal oxide semiconductor (CMOS) imager,located within the endoscope of the present specification. The cameraboard 521, in turn, receives at least one video signal 513 generated bythe image sensor 512 and optionally other remote commands 514 from theendoscope.

U.S. patent application Ser. No. 14/263,896, entitled “Video ProcessingIn A Compact Multi-Viewing Element Endoscope System” and filed on Apr.28, 2014 and U.S. Provisional Patent Application No. 61/936,562,entitled “Method and System for Video Processing in a Multi-ViewingElement Endoscope”, filed on Feb. 6, 2014 describes the remote commandsand associated video processing signals and are herein incorporated byreference in their entirety.

Controller unit 520 further comprises components for processing thevideo obtained from the image sensor 512, including MPEG digital signalprocessor 522 and field-programmable gate array (FPGA) local processor523 that performs video interpolation and on-screen display overlay. Thevideo signal is sent for display through video output interface 524. Avideo input interface 525 is also provided for receiving video inputfrom an external analog or digital video source.

System on module (SOM) 526 provides an interface for input devices suchas a keyboard and mouse, while touch I/F 527 provides touch-screeninterface functionality. Controller unit 520 may further control one ormore fluid, liquid and/or suction pump(s) which supply correspondingfunctionalities to endoscope 510 through pneumatic I/F 528, pump 529,and check valve 530. Controller unit 520 further comprises a powersupply on board 545 and a front panel 535, which provides operationalbuttons 540 and switch 541 for the user.

Camera board 521 receives video signal 513 which, in one embodiment,comprises three video feeds, corresponding to video pickups by threeendoscopic tip viewing elements (one front and two side-looking viewingelements), as generated by image sensor 512.

FIG. 5B shows a block diagram of an embodiment of a white balancecircuit 500 that is implemented as part of the controller unit 520 ofFIG. 5A. Referring now to FIGS. 5A and 5B, a plurality of video digitalsignal processors (DSPs) 570, either placed on camera board 521 or builtinto a CMOS sensor, receive a “white balance command” through element OR502. A “white balance command” is either produced by a timer 501 whichis controlled by an operator (physician) through a momentary electricalswitch 541 or produced by a controller 503 with a built-in timerconfigured to receive commands from system-on-module (SOM) 526. Thecommands are provided through a multi-master serial single endedcomputer bus 504, which, in various embodiments, comprises anInter-Integrated Circuit (I²C) or other standard bus communication,including parallel. In one embodiment, the “white balance command” isonly operator initiated. In various embodiments, the white balance timeperiod is typically a few seconds, such as 3-5 seconds, and can be othertime periods dependent upon the DSP.

Persons of ordinary skill in the art would appreciate that each of thethree video feeds 505 includes color image information comprising thethree primary color image signals—red (R), green (G), and blue (B), orfour additional color image signals—yellow (Ye), cyan (Cy), magenta(Mg), and green (G), for reproducing a color image.

For generating calibrated white balance values/factors, in oneembodiment, the three endoscopic tip viewing elements (one front and twoside-looking viewing elements) are directed to image a reference whiteobject to obtain/calculate baseline or reference white balancevalues/factors W_(R), W_(G), W_(B) for the corresponding three primarycolors or W_(Ye), W_(Cy), W_(Mg), W_(G) for the corresponding fouradditional colors. In accordance with an aspect of the presentspecification, a novel white balance enclosure (described below withreference to FIGS. 6A, 6B, 6C, 6D, and 6E) is used as a reference whiteobject to consistently and uniformly white balance each of the threeviewing elements of the endoscope. The endoscopic tip is inserted intothe white balance enclosure and the three viewing elements of theendoscope, along with the corresponding illuminators, are placed inoperation, described in detail in the following paragraph, to expose thethree endoscopic tip viewing elements to a uniform white surrounding,thus generating three corresponding test feeds. While described for anendoscope comprising three viewing elements, the white balancing processdescribed herein can be used for an endoscope having any number ofviewing elements.

Referring back to FIGS. 5A and 5B, after exposing the viewing elementsuniformly to the reference white surrounding, white balance switch 541(located on the front panel 535 of the main control unit) is pressed toactivate or cause the DSPs 570 to calculate white balance values/factorsW_(R), W_(G), W_(B) or W_(Ye), W_(Cy), W_(Mg), W_(G) corresponding tothe three primary colors or four additional color respectively, for eachof the three test feeds. The white balance values/factors are thenstored in an electronic memory element 555, such as electricallyerasable programmable read-only memory (EEPROM). Persons of ordinaryskill in the art would appreciate that the white balancing is directedto and performed on both still images as well as video signals generatedby the viewing elements of the endoscope. In other words, theaforementioned test feeds comprise both still images as well as videosignals.

In accordance with one embodiment, the white balance process isperformed by the DSPs 570. A white balance signal is a command for theDSPs 570 to perform white balance processing and is sent from the whitebalance circuit 500 to the plurality of DSPs 570 through a splitterelement 506. The previously calculated and stored white balancevalues/factors W_(R), W_(G), W_(B) or W_(Ye), W_(Cy), W_(Mg), W_(G) aresent to the DSPs 570 to independently amplify or attenuate therespective red, green, and blue signals or yellow, cyan, magenta, andgreen signals of each of the three video feeds 505 received by the whitebalance circuit.

FIGS. 6A, 6B, 6D and 6E are perspective views of a white balanceenclosure 600 of the present specification, while FIG. 6C is across-sectional view of a white balance enclosure 600 showing a multipleviewing elements endoscopic tip 620 positioned therein. Referring now toFIGS. 6A through 6E, in accordance with an embodiment, enclosure 600 isinternally designed as a cap (to conveniently slip/slide onto, bepositioned over, and enclose the multiple viewing elements endoscopictip 620) comprising first body portion or front portion 605 and secondbody portion or housing 610 that, in one embodiment, are substantiallycylindrical. Portions 605, 610 are of similar, identical, or differentshapes, such as and not limited to rectangular, square, or any othershape. It should also be noted that while the present specificationdescribes the white balance enclosure as being comprised of bodyportions, the enclosure may form a single, integrated body unit.

The second body portion 610, in one embodiment, is a housing defining anenclosed volume that has an opening 606, defined by at least partiallycoaxial first body portion 605, for receiving the endoscopic tip. In oneembodiment, the opening 606 has a circumference or diameter that isconfigured to snugly receive the endoscopic tip such that external lightis prevented from entering through the opening 606. The enclosed volumeof the housing has a surface area that is located at a pre-defineddistance from at least one second viewing element. Further, the enclosedvolume of the housing includes a member extending from the surface area(and positioned thereupon) to position the first viewing element at apredefined distance from the surface area.

In one embodiment, first portion 605 is positioned at, and housed atleast partially coaxially within, a front area of second portion 610.First portion 605 defines an opening 606, having a first diameter ‘d’,which leads into an inner area of second portion 610, having a seconddiameter ‘D’. In one embodiment, the inner area is substantiallycylindrical or spherical for receiving the endoscope tip. The distal endof second portion 610 is closed with a distal wall 611. The firstdiameter ‘d’ is configured to enable a multi-viewing elements endoscopetip 620, such as a two viewing elements (one front and one side-lookingviewing element) or a three viewing elements (one front and twoside-looking viewing elements) endoscopic tip, to be convenientlyinserted through and fit snugly into opening 606 and into a front areaof the second portion 610. The diameter ‘D’ is configured to ensure thatonce the endoscopic tip 620 lies within second portion 610, the distanceof endoscopic tip 620 (and therefore the multiple viewing elements) fromthe inner surfaces of second portion 610, including the distal wall 611,is equal to ‘t’. Therefore, in accordance with an embodiment, therelationship of the two dimensions ‘d’ and ‘D’ (respective ‘diameters’for the first and second portions 605, 610 in accordance with anembodiment) of the two portions 605, 610, respectively, is defined asD=d+2t. In various embodiments, the distance ‘t’ ranges from 10 to 12millimeters. In one embodiment, the distance ‘t’ is larger than 12millimeters.

In one embodiment, at least a portion of the surface area of theenclosed volume that is within the field of view of the second viewingelement is at least 10 millimeters.

Persons of ordinary skill in the art would appreciate that thedimensional relationship between the respective dimensions of the firstand second portions 605 and 610 ensures that portions of the outersurface of tip 620 lies at distance ‘t’ from the inner walls of secondportion 610. Thus, the side-looking viewing elements located on theouter cylindrical side surface of endoscopic tip 620 and thefront-looking viewing element located at the leading surface or distalface 615 of endoscopic tip 620 are maintained at a substantially uniformdistance ‘t’ from the inner walls of second portion 610.

An optional indicator marking 612 further facilitates/aids a leadingsurface or distal face 615 of endoscopic tip 620, and therefore thefront-looking viewing elements situated thereon, to be maintained at asubstantially uniform distance ‘t’ from distal wall 611. In someembodiments, the indicator marking 612 is a thin line engraved orembossed into the inner walls of second portion 610. In one embodiment,the indicator 612 is marked at a position such that when theside-looking viewing elements of tip 620 captures a view of theindicator, it should be understood by the user of the endoscope thatleading surface 615 is positioned at an appropriate distance ‘t’ fromdistal wall 611. In another embodiment, the inner walls of secondportion 610, including distal wall 611, has posts, protrusions, orstopper component(s) 613 that are positioned to meet endoscopic tip 620at its edges. Thus, positioning of tip 620 at a proper distance ‘t’ fromthe inner walls is facilitated by the use of physical structures,however, at the same time the viewing elements and illuminators andcorresponding fields of view remain unhindered (the fields of view arenot blocked).

In one embodiment, the inner surface are of the enclosure of the presentspecification is of a uniform color. In other embodiments, the innersurface area of the enclosure facing the fields of view of the first andsecond viewing elements is the same color. In other embodiments, theinner surface area of the enclosure facing the field of view of thefirst viewing element is of a first color and the inner surface area ofthe enclosure facing the field of view of the second viewing element isof a second color.

In one embodiment, once tip 620 is inserted into enclosure 600, theinner walls of second portion 610 and distal wall 611 together provide auniform reference white surrounding/background to the multiple viewingelements of endoscopic tip 620. Also, since each viewing element of tip620 is situated at a substantially uniform distance ‘t’ from the whitebackground, this facilitates simultaneous, consistent, and uniform whitebalancing of all of the multiple viewing elements of tip 620.Additionally, once tip 620 is positioned within enclosure 600, theinterior of enclosure 600 can be isolated from the influx of exteriorlight, so as to avoid creating uneven shadows and illumination in theinterior of enclosure 600. In one embodiment, enclosure 600 is made froma thermoplastic elastomer (TPE) and/or a thermoset elastomer to ensurean optimally light yet robust structure.

In one embodiment, enclosure 600 is an enclosure that can beslipped/slid onto endoscopic tip 620. In alternative embodiments,enclosure 600 is designed in the form of: a clasp that securely enclosesand attaches to endoscopic tip 620; a snap which snug-fits ontoendoscopic tip 620; or any other such suitable insertion structure thatwould be advantageously evident to those of ordinary skill in the art.Also, while in one embodiment enclosure 600 comprises cylindrical firstand second portions 605, 610, in alternative embodiments, the shape ofthe first and second portions 605, 610 is rectangular, square or anyother suitable shape that facilitates positioning of endoscopic tip 620(and therefore the front and side-looking viewing elements thereon) tobe equidistant from the inner walls of enclosure 600. Additionally,first and second portions 605 and 610 can be of different shapes—forexample, first portion 605 can be cylindrical while second portion 610is rectangular, square, or vice versa.

An outer surface 630 of second portion 610 comprises a connector that,in one embodiment, is a hanger 625 as shown in FIGS. 6A and 6B. Inanother embodiment, the connector is a coupler 626 as shown in FIGS. 6Dand 6E. When not in use, enclosure 600 is removably attached to a sideof the main control unit (such as main control unit 416 shown in FIG. 4)by mating hanger 625 with a corresponding plug located on the side ofthe main control unit, in accordance with an embodiment. In variousembodiments, hanger 625 connects with the corresponding plug bystructurally engaging with the plug or magnetically coupling with theplug. In another embodiment, enclosure 600 is integrated to a side ofthe main control unit (such as the main control unit 416 shown in FIG.4) by coupler 626. In one embodiment, when the white balance enclosureis connected to the main control unit via coupler 626, it is fixedlyattached. The endoscope is inserted into the white balance enclosurewhen attached and the calibration ensues. Persons of ordinary skill inthe art should appreciate that while the enclosure 600 is internallydesigned as a cap, in one embodiment, outer surface 630 can have anyshape, size and dimensions as would be ergonomically advantageous. Inother embodiments, the white balance enclosure may reside within themain control unit such that it is an integral part of the unit.

FIG. 7 is a flow diagram showing exemplary steps of one embodiment ofusing the white balance enclosure, internally designed as a cap inaccordance with an embodiment (and hereinafter referred to as the‘cap’), to simultaneously, uniformly, and consistently calibrate/whitebalance multiple viewing elements of an endoscopic tip. At 705, forwhite balancing, a physician or other operator of the endoscopic deviceinserts the multi-viewing elements endoscopic tip (such as an endoscopictip comprising three viewing elements—one front-looking and twoside-looking) through an opening of the cap. At 710, the physicianensures that the endoscopic tip is positioned within the cap such thatthe endoscopic tip is substantially equidistant from inner walls as wellas a distal wall of the cap. At 715, the multiple viewing elements,along with corresponding illuminators, are activated using appropriateinput commands to expose the multiple viewing elements simultaneously,uniformly, and consistently to a reference white surrounding within thecap. The image/video processing system generates white fields (testfeeds) corresponding to each of the multiple viewing elements.Thereafter, at 720, the white balance switch, located on a front panelof a main control unit, is pressed/activated by the operator (inputreceived from the system-on-module SOM) or activated by a predeterminedcommand signal to perform a white balance. At 725, digital signalprocessors (DSPs) calculate and store white balance values/factorsW_(R), W_(G), W_(B) or W_(Ye), W_(Cy), W_(Mg), W_(G) corresponding tothe three primary colors (Red, Green and Blue) or four additional colors(Yellow, Cyan, Magenta, and Green) for the test feeds of each multipleviewing element. At 730, the operator removes the endoscopic tip fromthe white balance enclosure. After use, at 735, the white balanceenclosure is placed along the main control unit. The cap/enclosure iscoupled to a side of the main control unit using a coupling mechanism,such as a hanger. The hanger may be attached to the cap or to the maincontrol unit.

The above examples are merely illustrative of the many applications ofthe system of present invention. Although only a few embodiments of thepresent invention have been described herein, it should be understoodthat the present invention might be embodied in many other specificforms without departing from the spirit or scope of the invention.Therefore, the present examples and embodiments are to be considered asillustrative and not restrictive, and the invention may be modifiedwithin the scope of the appended claims.

In the description and claims of the application, each of the words“comprise” “include” and “have”, and forms thereof, are not necessarilylimited to members in a list with which the words may be associated.

We claim:
 1. A method for white balancing of a first viewing element anda second viewing element in a tip of an endoscope, wherein the firstviewing element is positioned on a distal face of the tip and the secondviewing element is positioned on a side of the tip, the methodcomprising: inserting the endoscope tip into a housing, the housingincluding an opening leading into an enclosed volume, wherein theopening is configured to receive the endoscope tip such that externallight is prevented from entering through the opening when the endoscopetip is inserted therein, and such that a field of view of the firstviewing element and a field of view of the second viewing element areonly of an interior of the housing, wherein the endoscope tip isisolated from any influx of external light when positioned within thehousing; wherein the endoscope tip is inserted into the housing via theopening; positioning the first viewing element at a first predefineddistance from a first interior surface of the housing; white balanceprocessing images obtained by the first viewing element and the secondviewing element; and splitting a white balance command to a digitalsignal processor associated with said first viewing element and saidsecond viewing element.
 2. The method of claim 1 further comprisingdisplaying said images.
 3. The method of claim 1 comprising connecting acontrol unit to the endoscope, wherein the control unit comprises: awhite balance circuit for the white balance processing of imagesobtained by the first and second viewing elements; and a splitterassociated with the white balance circuit for splitting the whitebalance command to the digital signal processor associated with saidfirst viewing element and said second viewing element.
 4. The method ofclaim 1, further comprising controlling a time period of the whitebalance processing.
 5. The method of claim 4, wherein the time period isin a range from 3 to 5 seconds.
 6. The method of claim 1, wherein, uponpositioning the first viewing element at the first predefined distancefrom the first interior surface of the housing, the second viewingelement is positioned at a second predefined distance from a secondinterior surface of the housing.
 7. The method of claim 6, wherein thefirst predefined distance and second predefined distance are the same.8. The method of claim 6, wherein the first predefined distance andsecond predefined distance are different.
 9. The method of claim 1,wherein the portion of the first interior surface of the housing withinthe field of view of the first viewing element is a first color, whereina portion of a second interior surface of the housing within the fieldof view of the second viewing element is a second color.
 10. The methodof claim 9, wherein the first and second colors are the same.
 11. Themethod of claim 9, wherein the portions of the first and second interiorsurfaces of the housing within the fields of view of the first viewingelement and second viewing element have a white color.
 12. The method ofclaim 9, wherein a portion of the second interior surface of the housingis at least 10 millimeters from the field of view of the second viewingelement.
 13. The method of claim 1, further comprising positioning theendoscope tip within the opening using at least one indicator on asecond interior surface of the housing, wherein the indicator ispositioned on the second interior surface of the housing such that theat least one indicator is visible via the second side viewing element.14. The method of claim 1, further comprising forming the housing byjoining together a first portion of the housing and a second portion ofthe housing.
 15. The method of claim 1, wherein the interior of thehousing has a cylindrical or spherical shape.
 16. The method of claim 1,wherein the opening has a first diameter and wherein the enclosed volumeis defined by a second diameter equal to the first diameter plus twicethe first predefined distance.
 17. The method of claim 1 furthercomprising white balance processing of images obtained by a thirdviewing element positioned on a side of the tip of the endoscope,wherein the housing has a third interior surface that is at the firstpredefined distance from the third viewing element when the tip of theendoscope is inserted into the opening.
 18. A method for white balancingof a first viewing element and a second viewing element in a tip of anendoscope, wherein the first viewing element is positioned on a distalface of the tip and the second viewing element is positioned on a sideof the tip, wherein the endoscope tip includes a cover with acylindrical wall, a distal end wall at an end of the cylindrical wall,and openings in at least one of the cylindrical wall and the distal endwall for the first viewing element and the second viewing element, themethod comprising: inserting the endoscope tip, including at least aportion of the cover, into a housing, the housing including an openingleading into an enclosed volume, wherein the opening is configured toreceive the endoscope tip such that external light is prevented fromentering through the opening when the endoscope tip is inserted therein,and such that a field of view of the first viewing element and the fieldof view of the second viewing element are only of an interior of thehousing, wherein the endoscope tip is isolated from any influx ofexternal light when positioned within the housing; wherein the endoscopetip is inserted into the housing via the opening; and white balanceprocessing images obtained by the first viewing element and the secondviewing element.